1. Field of the Invention
The present invention relates to a substrate fixing apparatus in which a substrate such as a printed circuit board can be simply fixed in a main body of the product without separate fixture members.
2. Description of the Related Art
In general, a substrate such as a printed circuit board having various parts or a circuit pattern is mounted on the main body of an electric or electronic product or data communication system in order to achieve a given function.
FIGS. 1 and 2 show examples of a substrate fixing apparatus generally employed in the art. More specifically, in a conventional substrate fixing apparatus as shown in FIGS. 1A and 1B, a fixing groove 10b is formed by a bent portion 10a formed at both sides of a chassis 10 which is disposed in the main body of the product (only one side is seen in the drawing). A substrate supporting piece 11 formed with a guide groove 11a on one side, is fitted in the fixing groove 10b. At this time, an aperture 10c formed on the chassis 10 is aligned with a screw hole 11b formed on of the substrate supporting piece 11. A fixing screw 12 fastens the chassis 10 and the supporting piece 11. Then, a substrate 13 is inserted into the guide groove 11a of the supporting piece 11.
According to an another fixing apparatus as shown in FIGS. 2A and 2B, a plurality of substrate supporting pieces 20c, each having a screw hole 20b, are formed on a top portion 20a by cutting and bending both sides of a chassis 20 (only one side is seen in the drawings). The screw hole 20b of the supporting piece 20c coincides with a hole 21a formed on the substrate 21, and a fixing screw 22 fastens the chassis 20 and the substrate 21.
However, in the conventional substrate fixing apparatus as described above, since the holes are first provided on the chassis and the substrate and then are fastened by the fixing screws, it requires accurate operations to fasten the substrate and the chassis and a separate driver or electromotive tool is needed to fasten the chassis and the substrate. Further, the screw threads of the screw are likely to be defaced in disassembling or assembling the substrate on the chassis. As a result, the screw often turns freely in the holes.
For this reason, a technique in which the assembling procedure is simplified and costs are reduced is presently known. But it is also complicated in construction and it is difficult to disassemble the substrate fastened to the chassis.
Another substrate supporting technique is disclosed in Japanese utility model laid-open publication No. sho 63-164287, in which a substrate is placed on a base and an upper surface of the substrate is then fixed by virtue of a separate fixing member without using a fixing screw.
The technique disclosed in the publication is disadvantageous as it requires the assembling procedure executed between the substrate and the chassis, and an additional process step to adhere the fixing member.